“Traditionally, the word ‘decontamination’ has been applied to those cleaning procedures—automatic and/or manual—that take place prior to sterilisation. Recent documentation, however, has redefined the word to apply to the whole series of procedures to ensure that a device is made safe after use on one patient prior to use on a second. Decontamination can thus include cleaning, disinfecting and sterilising.” This statement is taken from an article published in the ISSM (Institute of Sterile Service Managers) Journal, Vol. 5, No. 1 Jul.-Sep. 2000. The statement helps to explain what the decontamination process has come to mean in modern UK hospitals and goes on to refer to HTM2030, which has been the driver for change in processing many types of medical instruments. The term ‘decontamination’ will be used herein to refer to the above redefinition, including cleaning and sterilising.
Health Technical Memorandum (HTM) 2030 was introduced in 1993 and updated in 1997 and 2001 to improve the sterile processing performance of washer disinfectors. HTM2030 addresses the use of washer-disinfectors for instruments, many of which cannot be autoclaved, for example flexible endoscopes. In essence, it describes the need to wash instruments thoroughly before disinfection/sterilisation (by heat or by chemical); to be followed by the disinfection/sterilisation stage and to culminate, in the case of chemical disinfection, in the rinsing of the instrument. HTM2030 also addresses the need for the entire process to be recorded in a traceability and audit system.
Two-part sterilising solutions are used in applications where the active sterilising ingredient is unstable over time. The solution is therefore prepared in situ shortly before it is to be used. A particularly important sterilising agent is chlorine dioxide, which may be formed from mixtures of various reagents including: chlorite and acid; chlorate, peroxide and acid; and chlorite, hypochlorite, and a suitable buffer. Chlorine dioxide has excellent sterilising and bactericidal properties, and oral ingestion in man and animals has been shown to be relatively safe.
The cleaning of endoscopes and other medical equipment with suitable chlorine dioxide solutions is known. See, for example, European Patent Number 0 785 719 and U.S. Pat. Nos. 5,696,046 and 6,007,772, the contents of which are hereby incorporated by reference.
It is not always convenient to mix up batches of solutions for use in sterilising equipment. For wiping down (rather than thoroughly cleaning inside and out) of endoscopes and probes, wipes of alcohol, general-purpose detergent, or soapy water are generally used, but these are not as effective as chlorine dioxide. It is desirable to be able readily to make up small quantities of two-component sterilising agents when desired and to be able to make such agents up in a form in which they may be readily handled for a particular application. It is particularly desired to provide a decontamination system which meets the HTM2030 standard.